United's penalty woes reached a head 10 days ago, when Rooney's effort in the replay win over West Ham went sailing over the bar.

It was their fifth spot-kick miss of the season, Rooney's second, and his 10th overall as a Red Devil.

And evidently, decisive action had been taken. With van Persie on the bench, it was Giggs who strode straight into the area once Mark Clattenburg had spotted Hughes handling Rooney's corner.

In more than two decades, the only times Giggs had missed in such situations were in shoot-outs, and though Mark Schwarzer got a hand to this one, the Australian was unable to keep it out.

The hosts should have had another when Giggs' pass for Patrice Evra rolled off Damien Duff's arm. Inexplicably, Clattenburg ruled this intervention accidental and Fulham's escape was complete when Schwarzer turned Rooney's shot onto the bar as the hosts pressed at the corner.

A neat move involving Anderson and Giggs presented Rooney with another chance, which Schwarzer blocked at his near post.

Fulham were almost exclusively bystanders to this one-sided game, with Dimitar Berbatov flickering only briefly, and then the applause he received on his return to the club he served for four years was due to a brilliant piece of control on halfway.

Shortly afterwards Sascha Riether drilled a long-range effort just wide, just the reminder United needed that their place in the last 16 was not assured, and which they rectified within five minutes of the restart.

Anderson deserved immense credit for his brilliant through-ball.

But the goal clearly meant something to Rooney, who turned inside Hughes then sent a ferocious shot flying past Schwarzer.

On United's next attack, Nani's trickery put Fulham's defence on the back foot before Rooney's cross ended up with Hernandez, who lashed home a close-range volley.

And midway through the half Hernandez had another, charging onto Giggs' pass before his shot deflected off Hughes and gave Schwarzer no chance.

It was the Mexican's fifth goal in six games, underlining the fact United are not quite as reliant on Van Persie as some people seem to think.

Not that everything went to plan for the hosts.

Having kept faith with under-fire David de Gea, Ferguson would not have been happy that the keeper's goal should be breached at a routine corner.

De Gea himself was not culpable but the ease with which Hughes rose at the near-post to steer home Giorgos Karagounis' corner was alarming for a side with only seven clean sheets all season.